Internal wrench



all

Patented Aug. 7, 1934 j 519683772 l f N Y IN'rERNAL wRENonjw C Roaneyncampbell, Walnut-'Para oa1if.,asl 1 signor `to* vAbraham M.

Park, Calif.

Herbsman, Huntington,

` Applumas 'Julyi'L `1933; seal ne. 678,639

2 Claims. (Cl. 81--7/2) My invention relates tofimproveinents ininternal wrenches and4 has forrits principal ob jects, to generallyimprove, upon and simplify the. construction of the existing formsofinternal wrenches and toprovide a wrench having dogs or jawsthat arecapable of being radiallyA projected or `retractedinl order `that theymay be readily vengaged with the internal face of a pipe, coupling orthe like forthe purpose of rotatingthe samewhile said pipe or couplingis being screwed into croutof a part or memberA to whichit is'connected.

- Further objects of my. invention are,`to provide an internal wrenchoflthe character referred to wherein the dogs or jaws haveinterengageinentwiththe `wrench member that is utilized for `projectingand retracting said dogs or jaws so that the latter cannot becomedetached from the wrench after `the samefhas been assembledY for useand-further, to construct the dogs or jaws and their carrier sothatsaid. dogs or jaws may be 'slightly .tilted circumferentially withrespect tothe axis of the wrench in order thatv one edge of each dog orjaw willzbe `positioned so as to engage and .bite into the inner surfaceof the pipe or` nipple that is being screwed or unscrewed. Y

A further object of my. invention is, to provide. an internal wrench.`of the character referred to that isl` relatively simple inconstruction, strong andrdurable and which comprises. rela-. tively fewparts that'are capable of being readily assembled or taken apartandfthejawsori dogs of which wrench are capable of being casily andquicklyadjusted so as to engage the inner,

surfaces of" pipes, nipplesV and ther like of` vary-v ing internaldiameters'. Y 1 .n

With the foregoing and other objects in View my inventionconsists incertain vnovel features of construction and arrangements of parts that.

.the center of an internalzwrench constructedjin` accordance with myinvention.`

Fig. 2 is a front elevational View ofthe wrench.- Fig. 3 is a crosssection taken en the jline :3a-3- of Fig. 1. i i

jaws or dogs. j Y, Fig. 5 is an end View of one of the dogs or jaws.

Referring by numerals to the accompanying drawing which illustrates apreferred embodimenti of Imy invention, designates the main bodyfoftheWrench, which is Vpreferably cylindrical inform and one endjof said bodyis. enlargedgto form ahead- -ll andthe peripheral face of ythis head isprovided with a plurality of fiat wrench; receiving faces12.

Formed in the forward portion of thebOdylO. is-an axially disposed' boreor chamber. 13 vand the rear end of `this bore communicates vwith anaxially disposed threadedl opening 1,4. that `is formed'through headll.Y l

' Formed in the forward portionofgbodyyl() isA a: plurality oflongitudinallydisposed slots and' the side faces ofl each .slotare-.preferably formed so that they diverge` slightly -towardthe outerface of the body. .i ff'. 1.

A short portion at `theforward end. ofrbody 10 is reduced in diameterasdesignatedby-lfi and the peripheral: face of this reducedfportion isthreaded for the reception of a ring'nut 17, theexternal diameter.ofwhich is substantially. equal tolthe external diameter of body lO'and;theperipheral face of this ringnut is knurled ori corrugated in orderthat it may be. conveniently gripped and rotated. j

. The externally threaded body 18 of a. sleeve or.` tubular memberisscrew-seated in the threaded; opening 14 rand. the outer end of thisVbody is enlarged to form-1.a head4 19 having wrench :rec eiving .faces2,0.Y i 1 Extending through the sleeve ortubular mem-v ber'l81is a'rodor shank 21 and detachab1ysecured to the end thereof that projects.beyond the rear end ofsleevev 18, is a ringor collar22`.;

Formed integral withV the forwardendof shank 21 is a cylindrical head23A that occupieslthe bore,

. or chamber 13 in the body ofthe tool and formedA in said head is aplurality of longitudinally disposed slots 24,.which gradually `increasein depth toward. the `forward end ofgsaid head.

The inclined bottom faces of these slotsare preferably flat and forrned`on the side faces of said slots adjacent` tof-and parallel with'thesatybottom :faces thereof, arci ribs 25Nthat project a short distance intothe slots. 1

The dogs or jaws utilized in :imprevedi-v wrench are :formed i of i`substantially vrectangular blocks, 26 of hardened ;metal,the thicknessof i A which isslightly less than thewidth-ofthe slots' Fig. 4 is a sideelevational View of oneofV the 24 inhead 23 and the slotsl Yin body 1'0andthe outer faces 27 of these dogs are disposed at right angles to theside faces thereof, thereby providing corners along both of the outerside edges of said dogs.

The inner or bottom face of each dog is inclined lengthwise tocorrespond with the inclination of the bottoms of the slots 24 and saidinner or bottom faces are rounded or made slightly convex in crosssection in order that said bottom faces may readily rock on the flatbottom faces of the slots 24.

Formed in the side faces of the dogs 26 adjacent to and parallel withtheir inner or bottom faces, are grooves 28 which receive the ribs 25that project from the side faces of slots 24 in head 23.

The engagement of the ribs 25 in the slots 28 retains the dogs upon thetapered head 23 and prevents the disengagement and loss of said dogsafter the tool has been properly assembled for use.

The ring nut 1'7 mounted on the reduced threaded forward end of the bodyretains the dogs against longitudinal movement through slots 15 in thetool body.

After the parts of the wrench have been assembled as illustrated in Fig.1 and with the inner ends of the dogs positioned in the slots 24 in head23, said head may be moved forwardly or rearwardly through chamber 13 byscrewing or unscrewing sleeve 18 through the rear portion of the toolbody.

As the head 23 is moved forwardly within the body, the engagement of theinclined bottom faces of the grooves 24 with the correspondinglyinclined inner faces of the dogs 26 will move said dogs radially outwardand likewise as head 23 is moved-rearwardly within the chamber 13 inbody 10, the dogs 26 will be retracted or drawn inwardly due to theengagement of the ribs 25 in grooves 28.

In the use of the Wrench, the forward end thereof with the dogs inretracted positions, is inserted in the end of the pipe or nipple to berotated and sleeve 18 is now screwed into the rear portion of the toolbody to move head 23 forwardly and such action projects the dogs 26until their outer edges engage the inner surface of the pipe or nipple.

By means of a wrench or other suitable tool applied to the faces 12 ofhead 11, the wrench is now rotated and in so doing the transverselycurved inner faces of the dogs 26 will rock on the fiat bottom faces ofgrooves 24 so that said dogs will tilt slightly circumferentially of thetool, thereby causing the corresponding outer edges of said dogs toengage and bite into the inner surface of the pipe or nipple andcontinued rotary motion of the body of the tool will impart rotarymotion to the engaged pipe or nipple so as to screw or unscrew the samewith respect to the part to which it is connected.

Thus it will be seen that as a result of my improved construction of thedogs or jaws and the means of mounting the same in the head 23, it isnot necessary to resort to any manipulations such as a reversal ofposition of the dogs or to interchange different forms of the dogs inorder to accomplish the screwing or unscrewing of the pipe, nipple orother part that is engaged by the wrench.

The tilting of the dogs as herein explained is automatically effectedfollowing the movement imparted to the body of the tool and thus one setof dogs may be used for both screwing and unscrewing operations.

When ring nut 17 is removed from the forward end of body 10, the dogs 26may be positioned within the slots in body 10 and the slots in head 23or removed therefrom by a longitudinal movement of said dogs relative tosaid head and body.

Thus it will be seen that I have provided an internal wrench that isrelatively simple in construction, inexpensive of manufacture and veryeffective in performing the functions for which it is intended.

It will be understood that minor changes in the size, form andconstruction of the various parts of my improved internal wrench may bemade and substituted for those herein shown and described withoutdeparting from the spirit of the invention, the scope of which is setforth in the appended claims.

I claim as my invention:

1. In an internal wrench, the combination with a body provided with anaxial chamber and with a plurality of radially disposed slots, of asleeve projecting into the rear portion of the axial chamber in saidbody and having threaded engagement with the rear portion of said body,a member carried by said sleeve and projecting into the forward portionof the axial bore in said body, the projecting portion of said memberhaving a plurality of slots having flat inclined bottoms, dogs arrangedfor sliding movement through the slots in said body the width of theslots in said body being slightly greater than the thickness of the dogsto permit the latter to tilt circumferentially of the body for a limiteddistance, the inner portions of which dogs occupy the slots in saidmember the bottom faces of which dogs are convex in cross section so asto rock transversely on the flat inclined bottoms of said slots andinterengaging ribs and grooves between said dogs and slotted member.

2. In an internal wrench, the combination with a body provided with anaxial chamber and with a plurality of radially disposed slots, of asleeve projecting into the rear portion of the axial chamber in saidbody and having threaded engagement with the rear portion of said body,a member carried by said sleeve and projecting into the forward portionof the axial bore in said body, the projecting portions of said memberhaving a plurality of slots having flat inclined bottoms, dogs arrangedfor sliding movement through the slots in said body the width of saidslots being slightly greater than the thickness of the dogs so as topermit the latter to tilt circumferentially of the body for a limiteddistance, the inner portions of which dogs occupy the slots in saidmember the bottom faces of which dogs are convex in cross section so asto rock transversely en the ilat inclined bottom faces of the slots,interengaging ribs and grooves between said dogs and slotted member,means removably mounted on the forward end of said body for retainingsaid dogs in the slots in said body and a collar removably mounted onthe rear end of the member that extends through said sleeve for holdingsaid member in operative relation with the sleeve and againstlongitudinal movement therethrough.

RODNEY B. CAMPBELL.

